Iron Man started the summer on May 2, and The Dark Knight signified the end with its release on July 18. Based on what we've seen in recent weeks - and the uninspiring upcoming release calendar - that's how Hollywood is marking the season these days.

The major new releases the past two weekends have ranged from the expired (The X-Files: I Want to Believe) to the tired (The Mummy: Tomb of the Dragon Emperor), with the requisite Will Ferrell comedy in Step Brothers and the movie with what might be the most annoying cast ever assembled in Swing Vote. (I can't imagine a more unholy film-acting trio than Kevin Costner, Kelsey Grammer, and Nathan Lane, and the movie still had room for Judge Reinhold?)

The Mummy and Step Brothers did just fine in their opening weekends, but they can't fool the Box Office Power Rankings. The Dark Knight is an unstoppable force with its combination of stellar reviews and record-breaking receipts, but the newcomers are even being bested by other older releases. This past weekend's major entries - The Mummy and Swing Vote - finished sixth and seventh, respectively, in the rankings, one hamstrung by abysmal reviews and the other sunk because nobody saw it. Step Brothers is performing strongly by our measures, while The X-Files looks to be the biggest miscalculation of the summer. Aside from Chris Carter needing the work, what was the point?

About Box Office Power Rankings

Box Office Power Rankings balance box office and critical reception to create a better measure of a movie's overall performance against its peers than gross receipts alone.

The weekly rankings cover the 10 top-grossing movies in the United States for the previous weekend. I assign equal weight to box office and critical opinion, with each having two components. The measures are: box-office gross, per-theatre average, Rotten Tomatoes (http://www.rottentomatoes.com) score, and Metacritic (http://www.metacritic.com) score.

Why those four? Box-office gross basically measures the number of people who saw a movie in a given weekend. Per-theatre average corrects for blockbuster-wannabes that flood the market with prints, and gives limited-release movies a fighting chance. Rotten Tomatoes measures critical opinion in a binary way. And Metacritic gives a better sense of critics' enthusiasm (or bile) for a movie.

For each of the four measures, the movies are ranked and assigned points (10 for the best performer, one for the worst). Finally, those points are added up, with a maximum score of 40 and a minimum score of four.